<p>The uplift behavior of short bored piles in completely decomposed granite (CDG) has not been systematically researched yet, particularly under dry drilling conditions where the mechanical responses at the pile-soil interface remains ambiguous. In this study, static uplift load tests coupled with subsequent on-site excavation and direct observations were conducted on three bored piles of varying lengths. The tests revealed the existence of a highly saturated disturbed soft soil layer around the pile shaft, which impeded the direct contact between pile concrete and CDG and thereby substantially reduced the unit skin friction. Based on the test results, a hyperbolic model describing unit skin friction development with relative displacement was proposed. To be specific, the unit skin friction increases with relative displacement in a hyperbolic manner initially and then approaches an ultimate value after reaching a critical displacement. Subsequently, a formula that incorporates factors such as disturbed soil properties, interface roughness, and embedment depth was proposed for calculating the ultimate unit skin friction and uplift bearing capacity of short piles. It is recommended to use different models to calculate the ultimate bearing capacity of piles under different length-to-diameter ratios (<i>L</i>/<i>D</i>, 15 as the boundary). The proposed formula was verified to be accurate and rational through a comparison to Chinese and American standards. The error of the proposed formula is less than 18%, which is much lower than the errors of 29% in the American standard and 27% in the Chinese standard. The research results are expected to deliver refined theoretical insights for the design of uplift piles in CDG regions and boast remarkable implications for engineering practice.</p>